passage of particles through matter (i) - …physicsweb.phy.uic.edu/482/lecture6.pdfpassage of...
TRANSCRIPT
References “Techniques for Nuclear and Particle Physics Experiments” Chapter 2 – by William Leo Particle Data Group Review: http://pdg.lbl.gov/2014/reviews/rpp2014-rev-quark-model.pdf http://pdg.lbl.gov/2014/reviews/rpp2014-rev-passage-particles-matter.pdf
wikipedia
Monday, February 16, 2015 2
High Energy Colliders
Monday, February 16, 2015 6
RHIC
NSRL LINAC Booster
AGS
Tandems
STAR 6:00 o’clock
PHENIX 8:00 o’clock
(PHOBOS) 10:00 o’clock
Jet Target 12:00 o’clock
RF 4:00 o’clock
AnDy 2:00 o’clock
EBIS
Radiation Detection • Charged particle: e±, µ±, τ±, u, d, s, c, b, t π±, K±, p±, α++, … W± • Neutral particles: νe, νµ, ντ, π0, K0, n, … γ, Z, g • Leptons: e±, µ±, τ±, νe, νµ, ντ • Quarks: u, d, s, c, b, t • Bosons: γ, Z, W±, g • Hadrons: π±, K±, p±, α++, π0, K0, n, …
Monday, February 16, 2015 8
Quark Model
Monday, February 16, 2015 10
Y - hypercharge 1/3 1/3 -2/3
Β – baryon number 1/3 1/3 1/3 1/3 1/3 1/3
0 0 0
http://pdg.lbl.gov/2014/reviews/rpp2014-rev-quark-model.pdf
Interaction Cross Section
Monday, February 16, 2015 12
differential cross section per target particle
total cross section
probability of interaction in δx
total interaction rate
mean free path
Classical Coulomb Cross Section
Monday, February 16, 2015 13
dσdΩ
dσdΩ
=b ⋅db ⋅dϕ
sinθs ⋅dθs ⋅dϕ=
κ 2
16E 21
sin4θs 2
V r( ) = 14πε0
qQr=κr
r θ( ) = p1+ε ⋅cosθ
p = L2 κm, ε = 1+ 2EL2 κ 2m
Energy Loss of Heavy Charged Particles Most likely: • Inelastic collisions with electrons of material nuclei σ~10-17-10-16 cm2
• Elastic scattering from nuclei Rare processes: • Bremsstrahlung • Cherenkov radiation • Nuclear reactions
Monday, February 16, 2015 14